Bobbin winding device

ABSTRACT

A bobbin winding device for generating a bobbin by winding a thread or bandlet onto a bobbin core comprises fixing means ( 12 ) for holding a bobbin core ( 8 ) and rotating it around an axis of rotation (A), thread-pressing means ( 7 ) for pressing a thread ( 1 ) or bandlet against the peripheral surface of a bobbin ( 9 ) that builds up on the bobbin core ( 8 ), whereby the thread-pressing means are movable essentially radially relative to the axis of rotation (A), a traversing thread guide ( 10 ) located close to the thread-pressing means ( 7 ) for reciprocating the thread ( 1 ) or bandlet along the axis of rotation (A), and thread-support means ( 14 ) for conducting the thread supplied to the bobbin or bobbin core, respectively, in an axially stationary manner relative to the axis of rotation (A). The thread-pressing means ( 7 ) are movable essentially radially relative to the axis of rotation (A) together with the thread-support means ( 14 ) so that the distance (z) between the thread-pressing means ( 7 ) and the thread-support means ( 14 ) will remain constant.

BACKGROUND OF THE INVENTION

The invention relates to a bobbin winding device for generating a bobbinby winding a thread or bandlet onto a bobbin core.

Bobbin winding devices serve for winding threads or bandlets onto abobbin core, which usually has a cylindrical or conical shape, so as toform a bobbin. In case of a known bobbin winding device as illustratedin side view in the schematic diagram of FIG. 1, a thread 1 gets to afirst deflection pulley 2 of the bobbin winding device immediately uponits production. From there, the thread 1 runs on to a so-called “dancerroll” 3, which is a spring-biased, deflectable deflection pulley, and atthe dancer roll it is deflected and tightened. From the dancer roll 3,the thread 1 runs on to another deflection pulley 4, and from there to acontrol device 5. The control device comprises thread deflection means6, which may be configured as deflection bows, as well as a press roll7, which at first, at the beginning of a bobbin winding process, pressesthe thread 1 against the peripheral surface of a bobbin core 8 and then,with a bobbin 9 building up from the supplied thread, against theperiphery of the bobbin 9 that is building up. The bobbin core 8 isrotatable around an axis of rotation A. A thread guide 10 reciprocatingthe thread axially across the bobbin, thus providing for a regularbobbin structure in accordance with a predetermined winding pattern, islocated on the control device 5 between the deflection means 6 and thepress roll 7. So as to maintain a uniform pressure force of the pressroll 7 against the bobbin 9 as the bobbin diameter D is increasing, thecontrol device 5 is pivotable about a swivel axis C and is thus able tocompensate for the increasing bobbin diameter. The arrow ρ(D) representsthe deflection angle of the control device 5 depending on the bobbindiameter D.

The bobbin 9 or the bobbin core 8 is driven by a motor (not illustrated)at an angular velocity Ω. The tension in the thread 1 as it is beingwound onto the bobbin 9 is critical for the quality of the bobbinwinding. If the tension in the thread slackens, the motor speed must beincreased in order to restore the desired tension. The dancer roll 3serves for regulating the motor speed, which dancer roll already byitself provides for a certain compensation of the thread tension due toits spring bias. An increase in the motor speed is caused if the dancerroll 3 sags because of decreasing tension in the thread 1. If the dancerroll 3 rises because of an increase in the thread tension, the motorspeed is reduced. Variations in the thread tension which necessitatechanges in the motor speed will occur if the bobbin diameter D increasesor if the thread production, and hence the supply of the thread to thebobbin winding device, accelerates or decelerates.

Another reason for variations in the thread tension is the axialmovement of the thread guide 10, such as explained by way of theperspective illustration of FIG. 2. FIG. 2 shows the path of the thread1 from the deflection pulley 4, via a deflection means 6 shaped like astraight deflection bow, through the thread guide 10 and, via the pressroll 7, onto the bobbin 9. If the thread guide 10 is at the axial endsof the bobbin 9 during its axial reciprocation, the thread 1 is guidedto the bobbin edge, thereby defining a path from the deflection pulley 4to the bobbin edge which is longer than with the thread guide 10situated at the center of the bobbin and with the thread 1 defining thepath from the deflection pulley 4 to the bobbin center (illustrated by abroken line). Due to the shortened thread path, the thread becomes looseat the center of the bobbin. As the axial movement of the thread isgenerally performed at a relatively high frequency, the resultingthread-tension variation cannot be compensated for by regulating therotational speed of the bobbin drive motor, since any kind of controlunit, such as a PID controller, would either be too slow or would, undersuch conditions, be prone to unstable oscillation, i.e. an unstablecontrol behavior. Therefore, so far it has been possible to contain theinfluence of the thread paths which have different lengths at the bobbinedge and at the bobbin center, respectively, on the thread tensionmerely by means of an as large as possible distance between thedeflection pulley 4 and the press roll 7. If the distance is larger, theangle extending between the deflection pulley 4 and the two positions ofthe thread 1 at the bobbin edges and hence also the factor (cosine) oflongitudinal deformation will become smaller.

Again with reference to the illustration of FIG. 1, it is evident thatthe thread-path length x(ρ) between the stationary deflection pulley 4and the deflection means 6 attached to the control device 5 changesdepending on the bobbin diameter D, since an increase in the bobbindiameter will result in a deflection of the control device 5 in thedirection of the deflection pulley 4. With a deflection of the controldevice 5, the distance z(ρ) between the press roll 7 located on thecontrol device 5 and the stationary deflection pulley 4 will change aswell. The distance y between the press roll 7 and the deflection means 6remains constant irrespective of the deflection of the control device 5.

The effects of incorrect thread tensions on the quality of the bobbinare enormous. The choice of thread tension for the winding process willnot be discussed in full detail now, however, in general terms it can besaid that an incorrect thread tension and in particular a varyingtension of the thread between the bobbin edge and the bobbin center willresult in a thread that falls off the edge of the bobbin, such asillustrated in FIG. 3. In FIG. 3 it can be seen that the thread 1 hasfallen off the edge of the bobbin 9 and onto the bobbin core 8 and wouldsubsequently wind itself around the bobbin core. This falling off of thethread might have an impact on the production capacity already duringthe process of manufacturing the bobbin and could lead to dead halts, ormight have an impact when using the bobbin later on, for example whenweaving the thread, and could then lead to dead halts or breakdowns.

The fact that the thread does not fall off is thus one of the mostimportant features of a bobbin. With the known bobbin winding devices itwas, however, difficult to fulfill that criterion in a satisfactorymanner. Particularly as a result of the high winding frequency, it wasnot possible to compensate for the varying thread tensions between thebobbin edge and the bobbin center by the use of motor control systems.

SUMMARY OF THE INVENTION

It therefore is an object of the invention to provide a bobbin windingdevice which avoids the above-indicated disadvantages and by means ofwhich it is possible to wind bobbins of a significantly increasedquality.

The bobbin winding device according to the invention for generating abobbin by winding a thread or bandlet onto a bobbin core comprisesfixing means for holding a bobbin core and rotating it around an axis ofrotation, thread-pressing means for pressing a thread or bandlet againstthe peripheral surface of a bobbin that builds up on the bobbin core,whereby the thread-pressing means are movable essentially radiallyrelative to the axis of rotation, with the thread-pressing meanspreferably being configured as a press roll with a longitudinal axisoriented in parallel to the axis of rotation, a traversing thread guidelocated close to the thread-pressing means for reciprocating the threador bandlet along the axis of rotation, and thread-support means forconducting the thread supplied to the bobbin in an axially stationarymanner relative to the axis of rotation. The solution according to theinvention consists in that the thread-pressing means are movableessentially radially relative to the axis of rotation together with thethread-support means so that the distance between the thread-pressingmeans and the thread-support means will remain constant. By thismeasure, the impact of the bobbin diameter which increases duringwinding on the thread tension is eliminated.

It should be mentioned that in the following description the term“thread” is mostly used. However, in this context, the term isunderstood to cover bandlets as well. As an exemplary embodiment of abandlet, a stretched single or multi-layer plastic bandlet is mentioned.

Furthermore, it must be mentioned that the bobbin core is usually anelement made of cardboard, a synthetic material or metal, which isattached to a rotatable fixing device and forms a carrier for the threadto be wound. However, in some applications, the fixing device can beconfigured as a spindle onto which the thread is wound directly and fromwhich spindle the bobbin is withdrawn upon its completion. In suchapplications, the term bobbin core as used herein refers to the spindle.

Although it is conceivable to arrange the traversing thread guidebetween the thread-pressing means and the thread-support means withoutany further thread support, for reasons of a smoother thread supply tothe bobbin it is preferable if at least one thread deflection means isarranged between the thread-pressing means and the thread-support means,which thread deflection means is movable radially relative to the axisof rotation together with the thread-pressing means and thethread-support means. The thread deflection means can thereby beconfigured as a thread-path compensating means which compensates for thedifferent lengths of the thread path from the thread-support means tothe thread-pressing means between the bobbin edge and the bobbin center,such as illustrated below in further detail. In a very robust andreliable embodiment, the thread-path compensating means is configured asa deflection bow which is curved at a predetermined radius. According tothe state of the art, the configuration of the thread-path compensatingmeans as a circular-arc-shaped deflection bow could be optimized onlyfor a particular bobbin diameter, wherein the radius of the deflectionbow was adjusted to the distance between the thread-support means andthe deflection bow, whereas thread paths of different lengths continuedto be provided at the bobbin edge and at the bobbin center if theparticular bobbin diameter was exceeded or fallen short of. According tothe invention, the distance between the thread-support means and thedeflection bow remains unchanged independently of the respectivediameter so that it will be possible to achieve a perfect thread-pathcompensation between the bobbin edge and the bobbin center for allbobbin diameters by means of a circular-arc-shaped deflection bow whoseradius is adjusted to the sum of thread paths from the thread-supportmeans to the deflection bow, and further on to the thread-pressingmeans.

In a preferred embodiment of the bobbin winding device according to theinvention, the thread-pressing means, the thread-support means andoptionally also the thread deflection means are pivotable about a commonswivel axis running in parallel to the axis of rotation of the bobbin.In a mechanically very stable and compact embodiment, thethread-pressing means, the thread-support means and optionally thethread deflection means are integrated in a control device which ispivotable about the above-mentioned swivel axis.

Great constructional reliability of the bobbin winding device isachieved if the thread-support means are configured as a roll or lug. Ina very robust embodiment of the invention, the thread deflection meansis configured as a deflection bow.

In a preferred embodiment of the bobbin winding device according to theinvention, a thread-tension sensor is arranged upstream of thethread-support means. However, unlike the prior art devices, thethread-tension sensor is not subject to any quick variations in thethread tension caused by different bobbin diameters so that its outputsignal can be used with great reliability for regulating the threadtension.

In a first mechanically simple embodiment, the thread-tension sensor isarranged in a stationary manner. In that embodiment, the deflectionangle of the thread on the thread-tension sensor would change for designreasons, which can be traced back to the positional change of thethread-support means in case of an increasing bobbin diameter. In thisway, the measuring results of the thread-tension sensor could beslightly falsified. In order to remedy this possible disadvantage, astationary thread deflection means can be arranged between thethread-support means and the thread-tension sensor in one embodiment ofthe invention.

In an alternative embodiment, the thread-tension sensor is arranged in amovable manner together with the thread-support means so that thedistance therebetween will remain constant. In this embodiment, theabove-mentioned problem of a varying thread deflection angle does notoccur in the thread-tension sensor.

In a preferred embodiment of the invention, the thread-tension sensorcomprises an arm with a strain gauge, with the arm carrying a threaddeflection means which preferably produces a deflection of the thread orbandlet by 150 to 180°.

By the measures according to the invention for preventing varyingthread-path lengths during the winding of the thread onto the bobbin andfor preventing high-frequency thread-tension variations as a resultthereof, it has become possible to use the output signals of thethread-tension sensor for controlling the bobbin motor. For thatpurpose, the output signals of the thread-tension sensor, which arerepresentative for the thread tension, are supplied to a control unit,preferably a PID controller, as input signals, which control unitregulates the rotational speed of the bobbin drive motor depending onthe input signals and a reference signal. By means of the electroniccontrol, the quality of the bobbins can be substantially improved.Preferably, the drive motor rotates the fixing device of the bobbin coreor the thread-pressing means.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be illustrated in further detail by way ofnon-limiting embodiments with reference to the drawings. In thedrawings:

FIG. 1 shows a schematic diagram of a known bobbin winding device;

FIG. 2 shows a thread deflection and pressing mechanism of the knownbobbin winding device;

FIG. 3 shows the effects of an incorrect thread tension during themanufacture of a bobbin;

FIGS. 4A and 4B show schematically a first embodiment of the bobbinwinding device according to the invention at different bobbin diameters;

FIG. 5 shows a thread-path compensating means as part of a bobbinwinding device according to the invention;

FIG. 6 shows the effectiveness of the thread-path compensating means ofFIG. 5 in comparison with a straight deflection bow;

FIG. 7 shows a block diagram of an electronic motor control of thebobbin winding device according to the invention;

FIG. 8 is a perspective view of a thread-tension controller of thebobbin winding device according to the invention;

FIG. 9 shows the geometrical correlations of the bobbin winding devicein FIG. 4B;

FIG. 10 shows the geometrical correction of angles of the deflectionpulleys on the bobbin winding device;

FIG. 11 shows a diagram of the thread strength depending on the bobbindiameter;

FIG. 12 shows the geometrical correlations of a further embodiment of abobbin winding device;

FIG. 13 shows the geometrical correction of angles of the deflectionpulleys on the bobbin winding device of FIG. 12;

FIG. 14 shows a diagram of the thread strength depending on the bobbindiameter of the embodiment of FIG. 12;

FIG. 15 shows the geometrical correlations of a further embodiment of abobbin winding device; and

FIG. 16 shows a diagram of the thread strength depending on the bobbindiameter of the embodiment of FIG. 15.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In FIG. 4A, a first embodiment of the bobbin winding device according tothe invention is schematically illustrated, which is an advancement ofthe known bobbin winding device according to FIG. 1. A thread 1 orbandlet gets to a first deflection pulley 2 of the bobbin winding deviceimmediately upon its production. From there, the thread 1 runs on to athread-tension sensor 13 equipped with a deflection pulley. Anembodiment of the thread-tension sensor 13 will be described below indetail. From the thread-tension sensor 13, the thread 1 runs on to athread-support means 14, which may be configured as a deflection pulleyrotatably mounted to an arm 15 a of a control device 15. The controldevice 15 furthermore comprises thread deflection means 6, which—such asin this exemplary embodiment—may be configured as straight deflectionbows, as well as a press roll 7, which at first, at the beginning of abobbin winding process, presses the thread 1 against the peripheralsurface of a bobbin core 8 and then, with a bobbin 9 building up fromthe supplied thread, against the periphery of the bobbin 9 that isbuilding up. The bobbin core 8 is rotatable around the axis of rotationA. A traversing thread guide 10 reciprocating the thread axially acrossthe bobbin, thus providing for a regular bobbin structure in accordancewith a predetermined winding pattern, is located on the control device15 between the deflection means 6 and the press roll 7. So as tomaintain a uniform pressure force of the press roll 7 against the bobbin9 as the bobbin diameter D is increasing, the control device 5 ispivotable about a swivel axis C and is thus able to compensate for theincreasing bobbin diameter. The arrow ρ(D) represents the deflectionangle of the control device 5 depending on the bobbin diameter D.

By means of the measure according to the invention of integrating thethread-support means 14 via the arm 15 a in the control device 15, thedistance x between the thread-support means 14 and the deflection means6 as well as the distance z between the thread-support means 14 and thethread-pressing means 7 will remain constant independently of theinstantaneous diameter D of the bobbin 9 and independently of theinstantaneous deflection angle ρ(D) of the control device 15, as opposedto the prior art bobbin winding device. This is best visible whencomparing FIG. 4A, wherein the bobbin 9 still has a small diameter D,with FIG. 4B, with FIG. 4B showing the bobbin winding device accordingto the invention of FIG. 4A at a later stage of the bobbin windingprocess, wherein the bobbin diameter has already substantially increasedand hence the control device has pivoted by a larger angle ρ(D).However, as can be seen, the triangle extending between thethread-support means 14, the deflection means 6 and the thread-pressingmeans 7 remains constant with its sides x-y-z, independently of thedeflection angle of the control device. Thus, the impact of the varyingbobbin diameter on the thread tension was successfully eliminated.

However, the embodiment of the bobbin winding device according to theinvention as in accordance with FIGS. 4A and 4B comprising a threaddeflection means 6 configured as a straight deflection bow stillexhibits the dependency of the thread-path length on the position of thethread at the bobbin center or at the bobbin edge, such as describedabove with reference to FIG. 2. In order to minimize this influence, alarge distance x between the thread-support means 14 and the threaddeflection means 6 and a large distance z, respectively, between thethread-support means 14 and the thread-pressing means 7 are necessary.

One possibility of completely compensating for the different thread-pathlengths at the bobbin edge and at the bobbin center is shown in aperspective view in FIG. 5 and is based upon the configuration of thethread deflection means as a thread-path compensating means shaped likea curved deflection bow 16, with the radius of curvature of thedeflection bow corresponding to the length L of the thread 1 between thethread-support means 14 and the deflection bow 16. If a curveddeflection bow was integrated in the embodiment of FIGS. 4A and 4Binstead of the straight deflection bow 6, the sum of distances x and ywould, at each deflection point of the thread, be constant relative tothe bobbin axis, whereas the distance y would decrease toward the bobbinedges. The effectiveness of such a thread-length compensation isillustrated in FIG. 6 by way of a comparison between a straightdeflection bow 6 and a curved deflection bow 16. It can be seen that, incase of the straight deflection bow 6, the thread path projects at thebobbin center beyond the deflection bow by a distance L1. This leads toa slackening of the thread tension each time the thread is located atthe center of the bobbin. Although the configuration of the threaddeflection means as a curved deflection bow 16 is known per se, themeasure obtains its full effectiveness only by means of the presentinvention, wherein the distance between the thread-support means 14 andthe deflection bow 16 remains constant independently of the bobbindiameter. According to the state of the art it was only possible tooptimize the radius of curvature of the deflection bow for a singlebobbin diameter so that, with every bobbin diameter that deviatedtherefrom, differences in thread-path lengths would continue to existbetween the bobbin edge and the bobbin center.

Again with reference to the illustration of FIG. 5, a motor 11 isschematically illustrated in the figure, which motor drives abobbin-core fixing device 12 shaped like a spindle, thereby rotating thebobbin 9 at an angular velocity Ω.

Such as initially mentioned, the tension in the thread 1 as it is beingwound onto the bobbin 9 is critical for the quality of the bobbinwinding. If the tension in the thread slackens, the motor speed must beincreased in order to restore the desired tension; if the tensionincreases, the motor speed must be reduced. Since by means of theinvention high-frequency variations in the thread tension are largely orcompletely eliminated when reciprocating the traversing thread guide 10,it thus becomes possible for the first time to use an electronic controlcircuit for regulating the motor speed, without the control circuitbeing prone to oscillations. By means of the electronic control it ispossible to adjust the desired thread tension much more exactly thanaccording to the state of the art where this was realized mechanicallyvia a spring bias on a dancer roll. The electronic control loop isillustrated schematically in the block diagram of FIG. 7. Thereby, themotor 11 rotates the bobbin 9 via the bobbin-core fixing device 12, thusgenerating a particular thread tension in the thread 1 that is woundonto the bobbin 9, which thread tension is scanned by the thread-tensionsensor 13 and is supplied to a control circuit 17 as an electricalsignal TS. The control circuit 17 may advantageously be configured as aPI controller or as a PID controller. If the control circuit 17 detectsthat the instantaneous thread tension deviates from a set value Ref, itgenerates (or changes) an output signal OS acting on a motor driver 18in order to adjust the rotational speed of the motor 11 such that thethread tension will be brought to the set value. Depending on the designof the motor 11, the motor driver 18 can, for instance, be configured asa static frequency converter.

In FIG. 8, an embodiment of the thread-tension sensor 13 is illustratedin detail. The thread-tension sensor 13 comprises a deflection pulley 13a positioned at the free end of an extension arm 13 b. The other end ofthe extension arm is securely fixed to a support 19. At about halflength of the extension arm 13 b, a strain gauge (DMS) 13 c is fixedwhich continuously measures the tension of the thread 1 running aroundthe roll 13 a. More precisely, the strain gauge 13 c measures thetension or upsetting deformation of the extension arm 13 b caused by thethread tension. The measuring signal generated by the strain gauge issubsequently used for regulating the rotational speed, such as explainedabove. The tensile force of the thread 1 which acts upon the deflectionpulley 13 a depends on the angle of the incoming and leaving thread endsrelative to the DMS measuring direction. Depending on the constructionaldesign, the angles change according to the bobbin diameter or remainconstant. In the following, a few variants will be described withreference to the drawings, wherein the geometrical correlation betweenthe variable bobbin diameter D and the thread force B(D) at apredetermined force S is illustrated analytically. S is the sum of theamounts of the thread forces B(D) which act upon the DMS and is constantin this case.

At first, the geometry of the bobbin winding device of FIG. 4B will beillustrated with reference to FIG. 9, which bobbin winding device has astationary deflection pulley 13 a of the thread-tension sensor as wellas a variable angle between the deflection pulley 13 a and thethread-support means 14. In the variant, the angle α remains constant.The size of the invariable portion of the incoming thread end depends onangle α and on the measuring direction ν of the thread tension. Theamount of the leaving portion is associated with the bobbin diameter.The dependency will be described below in detail. From FIG. 9, it can beseen that the angles α and γ must be corrected because of the radius ofthe deflection pulleys so as to maintain the force direction of thebandlets. The necessary correction of angles of the deflection pulleysis illustrated in FIG. 10.

The following quantities result via simple angle relations from theconstructively provided position parameters:

${\rho(D)} = {\arccos( \frac{R^{2} + {d\; w^{2}} - ( \frac{D}{2} )^{2}}{{2 \cdot R \cdot d}\; w} )}$κ(D) = ɛ − β − ρ(D)${{dmsb}(D)} = \sqrt{{db}^{2} + {dmsd}^{2} - {2 \cdot {db} \cdot {dmsd} \cdot {\cos( {\kappa(D)} )}}}$${\gamma(D)} = {{\arccos( \frac{{dmsd}^{2} - {{dmsb}^{2}(D)} - {db}^{2}}{2 \cdot {dmsd} \cdot {{dmsb}(D)}} )} - \mu}$

In consideration of the roll diameter, the angle γ(D) to γc(D) results(see FIG. 10):

${\gamma\;{c(D)}} = {{90{^\circ}} + {\gamma(D)} - {\arccos( \frac{r_{DMS} + r_{B}}{{dmsb}(D)} )}}$

In analogy to γc(D), αc to

${\alpha\; c} = {{90{^\circ}} + \alpha - {\arccos( \frac{r_{DMS} + r_{A}}{dmsa} )}}$results.

If the tilt of the force direction ν of the strain gauge (DMS) is addedor subtracted, respectively, to or from the above-indicated angles, thethread force B(D) can be calculated from the predetermined force S.

${B(D)} = {S \cdot \frac{1}{{\sin( {{\alpha\; c} + v} )} + {\sin( {{\gamma\;{c(D)}} - v} )}}}$

In FIG. 11, the course of the thread force B(D) is exemplarilyillustrated in Newton [N] depending on the bobbin diameter D in [m]. Theangle ν was chosen such that the DMS-force direction was the angularsymmetry of the thread force of roll 2 and the angular symmetry of thefinal positions at D=40 mm and D=180 mm of the thread-support means 14.Hereby, it must be considered that the angular symmetry of the thread tothe thread-support means 14 is not reached with an average bobbindiameter D=90 mm but only with a larger diameter D. However, there is adifferent reason behind the main factor of the asymmetry of the maximumforce: The force going to roll 2 being constant, the largestcontribution of the thread to the thread-support means 14 is obtained ifthe thread is positioned in parallel to the DMS-force direction, ratherthan if the DMS-force direction is positioned in the angular symmetry ofboth thread forces.

In FIG. 12, an embodiment of the bobbin winding device according to theinvention is illustrated which has a deflection pulley 13 a of thethread-tension sensor, which pulley pivots together with the controldevice 15, as well as a variable angle between the deflection pulley 13a and the stationary deflection pulley 2. The deflection pulley 13 a ofthe thread-tension sensor is connected with the control device 15 via anarm 15 b. In this way, also the DMS-measuring direction is distorted. Inthis variant, the angle α thus depends on the bobbin diameter. In thisvariant, the angle of the thread relative to the thread-support means 14and to the force direction of the DMS is constant. Instead, the angle ofthe DMS relative to roll 2 changes. In contrast to the previous variant,this variable angle not only depends on the bobbin diameter D but alsoon the height of the position of the bobbin winding device. Also in thiscase, the angles α and γ must be corrected, such as illustrated in FIG.13.

Hence, the following quantities result via simple angle relations fromthe constructively provided position parameters:

${\rho(D)} = {\arccos( \frac{R^{2} + {dw}^{2} - ( \frac{D}{2} )^{2}}{2 \cdot R \cdot {dw}} )}$κ(D) = β + ρ(D) − ɛ${dmsb} = \sqrt{{db}^{2} + {dmsd}^{2} - {2 \cdot {db} \cdot {dmsd} \cdot {\cos(\mu)}}}$${{dmsa}(D)} = \sqrt{{da}^{2} + {dmsd}^{2} - {2 \cdot {da} \cdot {dmsd} \cdot {\cos( {\kappa(D)} )}}}$$\gamma = {\arccos( \frac{{dmsd}^{2} - {dmsb}^{2} - {db}^{2}}{2 \cdot {dmsd} \cdot {dmsb}} )}$${\alpha(D)} = {{\arccos( \frac{{{dmsa}^{2}(D)} + {{dmsd}^{2}(D)} - {da}^{2}}{2 \cdot {{dmsa}(D)} \cdot {dmsd}} )} - \gamma - v}$

In consideration of the roll diameters, the angle γ to γc results (seeFIG. 10):

${\gamma\; c} = {{90{^\circ}} + \gamma - {\arccos( \frac{r_{DMS} + r_{B}}{dmsb} )}}$

From FIG. 13, αc(D) to:

${\alpha\;{c(D)}} = {{\alpha(D)} - {90{^\circ}} + {{\arccos( \frac{r_{DMS} + r_{A}}{{dmsa}(D)} )}.}}$results.

If the tilt of the force direction ν of the DMS is added to theabove-indicated angle γc, the thread force B(D) can be calculated fromthe predetermined force S.

${B(D)} = {S \cdot \frac{1}{{\cos( {\alpha\;{c(D)}} )} + {\cos( {\gamma + v - {\gamma\; c}} )}}}$

In FIG. 14, the course of the thread force B(D) is exemplarilyillustrated in Newton [N] depending on the bobbin diameter D in [m].

In another variant of a bobbin winding device according to the inventionas illustrated in FIG. 15, the deflection pulley 13 a of thethread-tension sensor is arranged in a stationary manner. By means of anadditional deflection pulley 19, a resulting constant force directionwill be achieved at the deflection pulley 13 a of the thread-tensionsensor. In the variant, the force directions of the thread forces remainconstant. Thus, they do not depend on the bobbin diameter D. Both anglesγc and αc must again be corrected:

${\gamma\; c} = {{90{^\circ}} + \gamma - {\arccos( \frac{r_{DMS} + r_{B}}{dmsb} )}}$

In analogy to γc, αc to

${\alpha\; c} = {{90{^\circ}} + \alpha - {\arccos( \frac{r_{DMS} + r_{A}}{dmsa} )}}$results.

If the tilt of the force direction ν of the DMS is added or subtracted,respectively, to or from the above-indicated angles, the thread force Bcan be calculated from the predetermined force S.

$B = {S \cdot \frac{1}{{\sin( {{\alpha\; c} + v} )} + {\sin( {{\gamma\; c} - v} )}}}$

In FIG. 16, the course of the thread force B is exemplarily illustratedin Newton [N]. It is evident that it is completely independent of thebobbin diameter.

1. A bobbin winding device for generating a bobbin by winding a threador bandlet onto a bobbin core, comprising: fixing means for holding abobbin core and rotating it around an axis of rotation (A),thread-pressing means for pressing a thread or bandlet against theperipheral surface of a bobbin that builds up on the bobbin core,whereby the thread-pressing means are movable essentially radiallyrelative to the axis of rotation (A), with the thread-pressing meansbeing configured as a press roll with a longitudinal axis orientedparallel to the axis of rotation (A), a traversing thread guide locatedclose to the thread-pressing means for reciprocating the thread orbandlet along the axis of rotation (A), thread-support means forconducting the thread supplied to the bobbin or bobbin core,respectively, relative to the axis of rotation (A), wherein thethread-pressing means is movable essentially radially relative to theaxis of rotation (A) together with the thread-support means so that thedistance (z) between the thread-pressing means and the thread-supportmeans will remain constant, with at least one thread deflection meansconfigured as a curved deflection bow being arranged between thethread-pressing means and the thread-support means, which threaddeflection means is movable radially relative to the axis of rotation(A) together with the thread-pressing means and the thread-supportmeans, wherein the thread deflection means is configured as athread-path compensating means and wherein the thread-support meansconduct the thread supplied to the bobbin or bobbin core, respectively,in an axially stationary manner relative to the bobbin (A).
 2. A bobbinwinding device according to claim 1, wherein the thread-pressing means,the thread-support means and the thread deflection means are pivotableabout a common swivel axis (C) running in parallel to the axis ofrotation (A).
 3. A bobbin winding device according to claim 2, whereinthe thread-pressing means, the thread-support means and the threaddeflection means are integrated in a control device pivotable about theswivel axis (C).
 4. A bobbin winding device according to claim 1,wherein the thread-support means are configured as a roll or lug.
 5. Abobbin winding device according to claim 1, wherein a thread-tensionsensor is arranged upstream of the thread-support means.
 6. A bobbinwinding device according to claim 5, wherein the thread-tension sensoris arranged in a stationary manner.
 7. A bobbin winding device accordingto claim 6, wherein a stationary thread deflection means is arrangedbetween the thread-support means and the thread-tension sensor.
 8. Abobbin winding device according to claim 5, wherein the thread-tensionsensor is movable together with the thread-support means so that thedistance therebetween will remain constant.
 9. A bobbin winding deviceaccording to claim 5, wherein the thread-tension sensor comprises an armwith a strain gauge, with the arm carrying a thread deflection means.10. A bobbin winding device according to claim 9, wherein the threaddeflection means produces a deflection of the thread or bandlet by 150to 180°.
 11. A bobbin winding device according to claim 5, whereinoutput signals (TS) of the thread-tension sensor, which arerepresentative for the thread tension, can be supplied to a control unitas input signals, with the control unit regulating the rotational speedof a bobbin drive motor depending on the input signals and a referencesignal (Ref).
 12. A bobbin winding device according to claim 11, whereinthe drive motor rotates the fixing device of the bobbin core.
 13. Abobbin winding device according to claim 12, wherein the control unit isconfigured as a PID controller.
 14. A bobbin winding device forgenerating a bobbin by winding a thread or bandlet onto a bobbin core,comprising: fixing means for holding a bobbin core and rotating itaround an axis of rotation (A), thread-pressing means for pressing athread or bandlet against the peripheral surface of a bobbin that buildsup on the bobbin core, whereby the thread-pressing means are movableessentially radially relative to the axis of rotation (A), with thethread-pressing means being configured as a press roll with alongitudinal axis oriented parallel to the axis of rotation (A), atraversing thread guide located close to the thread-pressing means forreciprocating the thread or bandlet along the axis of rotation (A),thread-support means for conducting the thread supplied to the bobbin orbobbin core, respectively, relative to the axis of rotation (A), whereinthe thread-pressing means is movable essentially radially relative tothe axis of rotation (A) together with the thread-support means so thatthe distance (z) between the thread-pressing means and thethread-support means will remain constant, with at least one threaddeflection means being arranged between the thread-pressing means andthe thread-support means, which thread deflection means is movableradially relative to the axis of rotation (A) together with thethread-pressing means and the thread-support means, wherein the threaddeflection means is configured as a thread-path compensating meanscomprising a deflection bow which is curved at a predetermined radiusand wherein the thread-support means conduct the thread supplied to thebobbin or bobbin core, respectively, in an axially stationary mannerrelative to the bobbin (A).
 15. A bobbin winding device according toclaim 14, wherein the thread-pressing means, the thread-support meansand the thread deflection means are pivotable about a common swivel axis(C) running in parallel to the axis of rotation (A).
 16. A bobbinwinding device according to claim 15, wherein the thread-pressing means,the thread-support means and the thread deflection means are integratedin a control device pivotable about the swivel axis (C).
 17. A bobbinwinding device according to claim 14, wherein the thread-support meansare configured as a roll or lug.
 18. A bobbin winding device accordingto claim 14, wherein a thread-tension sensor is arranged upstream of thethread-support means.